Some communication networks may be designed to operate in unlicensed frequency bands, such as various Industrial, Scientific, and Medical (ISM) bands in the United States. While some networks may be designed primarily for such use in the unlicensed bands, other networks operating in licensed bands may utilize the unlicensed bands to off-load traffic in some cases. For instance, demand for bandwidth in the licensed bands may be at or above capacity in a crowded area.
Operation in an unlicensed band is generally permitted for a device that has been certified as compliant with regulations governing the band, which may be created and enforced by a regulatory body such as the FCC. As such, it is possible that many devices of different types may be operating in an unlicensed band simultaneously and perhaps without any coordination between them. Naturally, the devices may interfere with each other, and may degrade overall performance and capacity of the band. As such, there are general needs for systems and methods for reducing interference and other effects between devices and for communication protocols that foster co-existence.